The present invention relates to an automatic vehicle speed control apparatus to conduct constant speed driving control when the headway distance to the preceding vehicle is equal to, or greater than a set value, and to conduct headway distance control when the headway distance is smaller than the set value, and more particularly to follow-up driving under the headway distance control.
The vehicles with (ACC) as an option are coming to be marketed in order to achieve driving comfort. The adaptive cruise control recognizes the behavior of the preceding vehicle by means of a laser radar or a millimeter radar and hereby implement automatic follow-up driving. when the headway distance is equal to, or greater than a set value, the own vehicle can run at a constant speed. When once the own vehicle has overtaken the preceding vehicle, the own vehicle can automatically run to maintain the set headway distance,
Additionally, Vehicle control with steering wheel control, inter-vehicle communications, road-to-vehicle communications, and other factors added to ACC in order to achieve fleet driving (driving in line) on expressways or automobile-dedicated roads and hereby to improve traffic efficiency and reduce drivers' burdens, is also proposed.
The above control system is disclosed in, for example, Japanese laid-open patent publications Nos. Hei 07-200991 and Hei 08-192662.